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@tsaniel
Forked from 140bytes/LICENSE.txt
Created November 7, 2011 14:03
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Fisher–Yates shuffle
function(
a, // an array
b // placeholder
){
for(b=a.length ;b ;)
a.push(a.splice(Math.random()*b--,1)[0]) // randomly move an element to the end
}
function(a,b){for(b=a.length;b;)a.push(a.splice(Math.random()*b--,1)[0])}
function(a){with(a)for(a=length;a;)push(splice(Math.random()*a--,1)[0])} // with version and save 1 byte thanks to @subzey
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
Version 2, December 2004
Copyright (C) 2011 YOUR_NAME_HERE <YOUR_URL_HERE>
Everyone is permitted to copy and distribute verbatim or modified
copies of this license document, and changing it is allowed as long
as the name is changed.
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0. You just DO WHAT THE FUCK YOU WANT TO.
{
"name": "shuffle",
"description": "Shuffle an array.",
"keywords": [
"Fisher–Yates",
"shuffle",
"array"
]
}
<!DOCTYPE html>
<title>Foo</title>
<div>Expected value: <b>Random numbers</b></div>
<div>Actual value: <b id="ret"></b></div>
<script>
// write a small example that shows off the API for your example
// and tests it in one fell swoop.
var myFunction = function(a,b){for(b=a.length;b;)a.push(a.splice(Math.random()*b--,1)[0])}
var a = [1,2,3,4,5,6,7,8,9];
myFunction(a);
document.getElementById( "ret" ).innerHTML = a
</script>
@williammalo
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you can make it shorter

function(a,b){for(b in a)a.push(a.splice(Math.random()*b,1))}

@tsaniel
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tsaniel commented Mar 21, 2012

@williammalo: Thanks for you advice!
But I am afraid that there will be an error if you input a non-array object.

@williammalo
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@tsaniel: "for in" loops also work with objects, for example: {foo:bar,lorem:ipsum} if thats whats bothering you.
If you don't change your own function, I'll make a fork =D

@tsaniel
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tsaniel commented Mar 22, 2012

I think an object does not have methods "push" and "splice"...
Anyway, feel free to fork the code :)

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